Spark-plug.



D. M. SWEENEY..

snm: nua. APPLICATIUII HLED HAV 25. lll- 1,317,834. Patented ocrh7,1919.

m'eulozj DarueUZ. Sweeney.

DANIEL IMI. SWEENEY, 0F SOTH BEND, INlIANA.4

SPARK-PLUG.

Bpeeication of Letters Patent.

Patented oct. 7, 1919.

Application nled' May 25, 1918.` Serial No. 236,467.

Ty all whom t may concern:

Be it known that I, DANIEL M. Swnnunr, a citizen fof the United States,residing at South Bnd, in the county of St. Joseph, in'

the State of Indiana, have invented certain new and useful Improvementsin Spark- Plugs, of which the following is a speciication'.

This invention relates to improvements in spark plu s and sparkingcircuits, and has for one o its objects to increase the intensity of thevspark by includinv in the circuit a form of condenser, an whichcondenser is preferably located within the spark plug structure.

To the attainment of these ends and the accomplishment of other new anduseful objects as will appear the invention consists in the features ofnovelty in substantially the construction, combination, and arrange#ment of the several parts, hereinafter more fully described and claimed,and shown in the accompanying drawing illustrating this invention, andin which:

The figure is a vertical longitudinal se@ tional view of the spark plugconstructed in accordance with the principles of this invention.

Referring more particularly to the drawing, the numeral 10 designatesthe metallic easing connected with which is one of the terminals of theplug-41. Arranged within the casing, located preferably in the lowerportion thereof is an insulating element l2 having secured therein andextendin therethrough the other terminal 13 which terminates adjacent tobut is spaced from the terminal 11 to form. a spark ap. The insulatingclement 12 is prefere ly hollowr as at 14 adjacent the end of theterminal 13 so as to form an air gap, and the insulating element .12 issecured in position in the casin in any desired or suitable manner suchasgby means of a fastening nut 15 arranged in the upper portion of thecasing and which nut has engagement with internal threads 16. Theinsulating material 12 and the nut 15 are spaced from the top of thecasing 10 and which portion of the casing above the nut forms a chamberin which is arranged a condenser of any suitable con struction, butpreferably constructed in the form of n Leyden-jar which comprises acontainer 17 constructed of insulating ma teriul auch as glass or thelike and is provided with an electric conducting eoatniz 18,

such as tin foil or the like on the inside thereof and which coatingterminates shoi't of the to of the container. A. similar electrlc conucting coating 19 is arranged on the outside of the container and alsoterinmates short of th'e to i of the container so as to be out ofelectrical connection with the coatmg'lS. The container is placed withinthe top of the plug and is insulated from the walls thereof by means ofsuitable insulating material 20 fand which insulating-` material alsoextends between the bottom of the container and the nut 15. The terminal13 extends through the insulating material 20-and has contact with theconducting coating 19 on the outside of the con. tainer 17. y

The cap ofthe insulating material 21 is removably secured to the casingso as to close the upper portion thereof, and 'a terminal 22 extendsthrough this cap into the plug. The terminal 22 is supported in anysuitable manner such as by means of a nut 23 engaging the` threadextremity thereof and a. binding post 24 is also threaded upon theterminal 22. Connected with the post 24 is a conductor 25 which leads tothe source. A flexible element 26v is connected with the threadedextremity of the terminal 22 and is arranged within the plug, with theend of the terminal 22 projecting into the container and terminatingshort of the top thereof while the flexible extremity 26 has contactwith the inner coating 18.

With this improved construction it will be seen that a very efficientplug is produced, the eflieiency thereof being materially increased andthe spark being intensified by the condenser whichis arranged within thelug and which, in the present form of the invention has been illustratedas being of the Leyden-jar construction.`

It will also be manifest that the parts of the plug may be readilyremoved or separated when desired.

Obviously, the terminal 13 is insulated -from the nut 15 to preventshort circuit, and to that end there may be provided an insulating plug15* arranged in the nut 15 and through which insulating plug the end ofthe terminal passes.

What is claimed as new is 1. A spark plug embodying a condenser therein,the two opposite plates of the condenser bving respectively inelectrical conneetien with the opposite polen of the plug,

one 0f the said connections embodyinv n, metallic terminal provided witha lcxi le section eontactin and resting against one of the plates of econdenser.

2. In a. spark plug en inclus-ing conducti easing, e termina electrical]connected w1 eding ueoniiuctor wit in and insulated from the casing,.the eltnemity of said conductor terminating adjacent the saidtenminaLnnd constituting-therewith n spark gpg', emewonnduotingcontainer within the cesing, mid container .having electric conductingcoating on the outside fthereof and with whichfeoating Fthe rst seidconductor has .electrical connection, said container alsohevingcnielectric conducting coating in the insidethcleaf Out electriccommunication with thecoating on the-outside thereof, and a. `conductorextendn in'to the container and lhaiving a flenib4 extremity restingfreely-a inst -and having electrical-connection .Wl the Vsaid coating onthe Vinterior of .the container.

3. In =e epark plug, an inelosing yconducting casing, a terminalelectricallyoonnected with the casing, a conductor within and insulatedfrom the casing, the extremity of said conductor terminating ed'acentthe seid terminati and constituting t erewith a spark gap, anon-conducting container withini the casing, seid container havin anelectric conducting coating on its insi e and on ins outside, saidcoatin bein out of electric connection, the said con uctor havingelectric connection `with the outside coating, n, conductor extendinginto the casing and having nsource of supply -of electric cnrrent, theend of the last .recited conductor extending into the container out ofcontact with the walls thereof, and n. vflexible -eonducting sectionconnected with ithe last recited conductor and' contactingl with l:theinside coating. y

4. In a spark plu aLeyden-jar structure formin part an parcel of thep'lugoand of the spar ing circuit, the :circuit em dying a conductorhaving a =fiexib1e section contacting and resting upon :the inner coatfing of the said jar structure.

In testimony whereof I .have signed my name to this specification, mthis16th day of May, A. D. 1918.

DANIEL M. SWEENEY.

